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I have two bulbs, say bulb 1 and bulb 2, also two switches, say switch 1 and switch 2.

I want the wiring to be such that when switch 1 is turned, both bulbs light up but when switch 2 is turned, only bulb 2 will light up.

Why I need this?

There is an area, from where after returning people forget to turn off bulb. Another bulb when lit up on the way is good way to remind them to turn off light. The bulb on the way should work independently but the bulb in the area should be dependent.

What I can do

I am ready to make circuits(with components) if they aren't commercially available. Also, advanced options like sensors or remote controls, I don't want to use.

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  • 1
    If switch 1 turns on bulb 2, do you want is wiring so that switch 2 can't turn off bulb 2, it would have to be turned off by switch 1?
    – HandyHowie
    Oct 5, 2022 at 9:05
  • 3
    A simple, dumb motion sensor seems like a much simpler answer. Doesn't require any sort of home automation, internet access or anything else. When it detects motion, it turns on. When it no longer detects motion (for a built-in switch defined amount of time), it turns off.
    – FreeMan
    Oct 5, 2022 at 11:32
  • 1
    If I have this straight, you want Light 1 to be solely controlled by Switch1 (switch2 has no effect on it) and Light2 should always be on if Switch1 is on or Switch2 is on (only off if both are off)? If so, then Switch1 directly controls Light1 and Switch1 and Switch2 are in an 'OR' configuration with Light2.
    – Glen Yates
    Oct 5, 2022 at 14:47
  • 1
    If my previous comment is correct, then you can easily wire this up with the only special equipment needed being a double pole switch (as opposed to a typical single pole) for Switch1.
    – Glen Yates
    Oct 5, 2022 at 15:14
  • 3
    Why not tie the bulbs together and use 3-way switches? You'll have the switch available in both places to allow light to be turned on, and when you turn off the "obvious" light, the "hidden" light is also taken care of
    – maples
    Oct 5, 2022 at 18:07

3 Answers 3

1

This digram shows the electrical connections you need

how you convert that into wires depends on your circumstances

enter image description here

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  • 2
    -1. I don't see how this resolves the OP's problem, despite his checkmark. In the current switch config, SW1 controls both lights (off). However, throw SW2, and L2 turns on, SW1 has zero control over that. SW1 open or closed has no control if SW2 is connected pin 2 to pin 3. If SW1 were a double-pole, double-throw switch on both the red & black lines, then it would control both, turning L2 on/off based on the position of SW2, but this won't work as is.
    – FreeMan
    Oct 6, 2022 at 11:50
  • @FreeMan I think this answer solves the purpose. If pin 2 to 3 is connected of SW2, it will make L2 independent of SW1, that's what I mentioned in the question. Putting it more simple there should be no way to turn L1 on and L2 as off. With SW1 as double pole double throw, this would not work.
    – Darpan5552
    Oct 6, 2022 at 16:33
  • +1 This diagram exactly matches the description in my answer. Oct 6, 2022 at 19:23
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    @FreeMan: I don't think it resolves the OP's problem either -- but it satisfies his specification. Oct 6, 2022 at 19:28
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    Glen Yates: Yeah, that's why your circuit is better than this one -- yours radiates fewer Bf/Wh. Oct 7, 2022 at 17:49
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Here is my understanding of the querent's requirements:

Switch 1    Switch 2    Bulb 1      Bulb 2
-----       -----       -----       -----
 Off         Off         Dark        Dark
 Off         ON          Dark        LIT
 ON          Off         LIT         LIT
 ON          ON          LIT         LIT

This can be wired with some of the same equipment used for a "three-way" circuit.

In the following I assume power arrives at switch 1. I also refer to the "line" and "load" terminals on a simple switch -- these are not marked, just choose.

Run a 14/3 (or similar) cable between the switch boxes. I assume the colors are white, black, red.

At switch 1 connect the service neutral to the neutral wire to bulb 1 AND to the white wire in the 14/3 cable. Install a simple ("two-way") switch. Connect the service hot to the "line" terminal on the switch AND to the black wire of the 14/3 cable. Connect the "load" terminal on the switch to the hot wire to bulb 1 AND to the red wire in the 14/3 cable.

At switch 2 connect the white wire in the 14/3 cable to the neutral wire to bulb 2. Install a "three-way" (single-pole double-throw) switch. Connect the common terminal on the switch to the hot wire to bulb 2. Connect one traveler terminal on the switch to the black wire in the 14/3 cable. Connect the other traveler terminal on the switch to the red wire in the 14/3 cable.

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    A drawing would go a long way toward helping with understanding your answer.
    – FreeMan
    Oct 5, 2022 at 18:19
  • I'd hesitiate to suggest a wiring gauge until I knew what size breaker the circuit was to be connected to.
    – Jasen
    Oct 6, 2022 at 20:28
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Ok, this is what I was envisioning, please excuse my PowerPoint drawing skills. This will implement the logic expressed in my comments to OP and as laid out in the table in the answer by A. I. Breveleri.

Switch 1 is a double-pole switch (not a 3-way) and Switch 2 is a regular single pole. Assuming a 15 amp circuit, all the cables are 14/2 except the cable which goes between the junction boxes which is 14/3.

Note: Ground wires are not shown for clarity. 2 Switches 2 LIghts

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  • This is what I do now that Reddit sucks. This is definitely more interesting so no regrets. Your drawing skills are on point.
    – jqning
    Jul 26, 2023 at 3:44

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